Snowmobile drive trains often use a variable ratio pulley that has a belt running between two sheaves between which the separation can be controlled by sheave rotational speed. The driven clutch in a variable gear ratio drive train includes a torque bracket to regulate the force required to separate the sheaves. This concept is well-illustrated in U.S. Pat. No. 3,800,608 to Bessette. This patent illustrates cooperating ramps that cooperate to regulate the force required to separate the sheaves depending on the rotational speed of the engine. A problem exists with the Bessette structure, because the slope of these fixed ramps can not be changed to vary the functioning characteristics of the drive train.
Another patent, U.S. Pat. No. 5,209,703 to Mastine et al. illustrates a mechanism to change the slope of a ramp used in a variable ratio drive pulley, but this patent requires the removal of the existing clutch mechanism and replacing it with a new mechanism as shown in this patent. The mechanism shown in Mastine et al. will not work with triangular ramps similar to those shown in U.S. Pat. No. 3,800,608.
What is needed is a torque bracket used with a variable diameter V-belt driven clutch which torque bracket includes a mechanism for easily adjusting the slope of a triangularly shaped ramp to vary the functioning characteristics of the drive train. Further, a need exists for an adjustable-slope torque bracket which can be used to easily replace a torque bracket used in a conventional driven clutch.